First there was an opportunity......then there was a betrayal. Twenty years have gone by. Much has changed but just as much remains the same. Mark Renton (Ewan McGregor) returns to the only place he can ever call home. They are waiting for him: Spud (Ewen Bremner), Sick Boy (Jonny Lee Miller), and Begbie (Robert Carlyle). Other old friends are waiting too: sorrow, loss, joy, vengeance, hatred, friendship, love, longing, fear, regret, diamorphine, self-destruction and mortal danger, they are all lined up to welcome him, ready to join the dance.

A wild, freeform, Rabelaisian trip through the darkest recesses of Edinburgh low-life, focusing on Mark Renton and his attempt to give up his heroin habit, and how the latter affects his relationship with family and friends: Sean Connery wannabe Sick Boy, dimbulb Spud, psycho Begbie, 14-year-old girlfriend Diane, and clean-cut athlete Tommy, who's never touched drugs but can't help being curious about them...